Sheet feeder



y 1940- H. T. BACKHOUSE 2.200. 08

SHEET FEEDER Filed Dec. 4, 1957 2 Sheets-Sheet l INVENTOR #54045) 75w/vsn/o Baa/mouse ATTORNEYfi M y 1940- H. T. BACKHOUSE 2.200.408

SHEET FEEDER Filed Dec. 4, 1957 2 Sheets-Sheet 2 1 N VE N TOR. #59045) firms/5x10 5000/01/55 Patented May 14, 1940 UNITED STATES PATENT OFFICE Slim!" manna Headley Townsend Boathouse, London, England Application December 4, 1987, Serial No. 178,129

In Great Britain June 26, 193'! 4 Claims. (01. 211-53) This invention consists of improvements in. or One specific embodiment of the invention will relating to sheet feeders and is partioularly'but now be described by way of example and with not exclusively concerned with automatic stream reference to the accompanyin i mm i feeders for printing or like machines, 1. e., feeddrawings, in which:

ers which supply sheets of paper, card or the like Fig. 1 illustrates the mechanism in side eleva- 5 to the machine in the form of a continuous tien n t e pos ti n o re istrat o o a s eet by stream of partly underlapped sheets. the front lays.

The invention has reference to the front lays Fi 2 is a imil r Vi w illu r the positi n which are normally provided for registering the of the mechanism during the feeding of the sheet sheets in position onthe feed board before they to h P n m hine- 10 are taken to the printing machine by means of Fig. 3 is a similar view illustrating the eng gegrippers or the like. In one common type of. ment of a misplaced Sheet y the ppin r printing machine the front lays operate above hol in evi and the feed board and, in turn, first engage and Fig. 4 is an end view on the line 4-4 of Fig. 1.

register in position the leading edge of each Inthis example the sheets I are fed down the sheet and then move away to release the sheet for fe heard 2 from a Stream feeder w h m y feeding to the printing machine. A difllculty be o t d de d in y cope di e appliwhich arises with this form of front lay mecha- Cation Serial 738500, d August 1934) nlsm is that should a sheet arrive on the feed in p r y pp d f mation. In the normal board in advance of its correct time and posiop t of th e a sm the leading edge of 20 tion there may not be time for the front lays, the top sh is n a ed s it reaches the end of after they have moved away from the registering the feed board by the f o t y 3 Wh ch efiect position to release the preceding sheet, to return the longitudinal registration f h sheet- At to that position before the leading edge of the t pp p a t me i the cycle of p rations of abnormally advanced sheet has moved past the h P n hine the leading sheet is taken 25 registering position. If this should happen then by r ppers (not shown) and the front lay 3 the advanced sheet may not be properly gripped swing ab ut h axis 4 nto the position shown by the feeding grippers and it may be tak n i t in Fig. 2 and the sheet is transferred to the imthe machine in a torn and crumpled condition pression roll 5.

80 and possibly at the same time cause damage to Shortly after the leading sheet has been taken 80 the machine. It is an object of the present inby the grippers the hook-like stops 6 move upvention to provide improved mechanism by which wardly into the position shown in Fig. 2, lifting this dificulty is overcome. the leading sheet off the feed board. Imme- In the embodiment of the invention herein ildlately after the trailing edge f the Shee ha lustrated, a. sheet-fed printing or like machine left the feed board the front lays 3 return to the 35 is provided with front lays operating as described registering position and in the normal Operation above to register the leading edge of each sheet of the ma hi e th y reach at p t in ti in turn and is characterized by one or more to engage the lead n ed e o t e succeedin sheet-arresting devices operating from below the sheet. If, how the Succeeding he has b n in level of the feed board and arranged to be oper. misplaced on the conveyor of the feeding mechaative, during the whole or part of the time the nlsm its leading edge may arrive at the registerfront lays are moved out of the sheet registering ing position and move past that position before position for the release of the leading sheet, to there has been time for the front lay to et engage and prevent the feeding substantially to it. past the registering position of a succeeding sheet. The sheet will, however, as shown in Fig. 3, be 45 In the preferred form of the invention the engaged by the stops 6 which are located closely sheet arresting device comprises a stop or stops adjacent to the registering position and which located close to the front lay registering posiprevent substantial movement of the sheet past tion on the side thereofnearer to the machine that position. This will occur even should the in the direction of movement of the sheets and sheet have been misplaced to such an extent that 50 upwardly movable to a position above the level of it underlaps the trailing edge of the preceding the feed board to engage, and prevent further sheet when it reaches the end of the feed board. feeding movement of, a sheet which may be fed On the return of the front lays they may either past the registering position until the front lays push the sheet back into position or, depending have returnedtothat position. upon the thickness and weight of the sheet, 55

slightly buckle it. In either case the sheet will be presented to the grippers of the machine in such a manner that it will pass through the machine without damage although it may be slightly out of register. Immediately after the front lays have returned to the registering position the stops 6 move downwardly below the level of the feed board to allow the sheet to be taken by the grippers and moved over the stops.

The movement of the front lays and the stops may be effected from any suitable moving part of the printing machine or of the sheet separating and feeding mechanism. By way of example I have shown herein a shaft H3 upon which are mounted two cams H and i2, cam ll engaging a follower l3 carried by a bifurcated arm Hi which is pivotally connected with one of the front lays 3, the bifurcations straddling shaft l so as to be slidable thereupon but guided and supported thereby. Cam I? acts upon a follower l5 carried upon one end of a crank arm 16 which is fixed to a shaft l1 upon which the stops 6 are also mounted. The shaft in is so driven as to have one revolution for each revolution of the impression cylinder 5, and it may conveniently be the same shaft that operates detector mechanism (not shown) for stopping the printing machine should no sheet be presented at the proper time for feeding to the machine.

It is to be understood that the invention is not restricted to the precise constructional details set forth. Thus the front lays may be of the kind having a substantially vertical movement towards and away from. the feed board. In that case the front lays will not operate to push back a sheet which has been fed slightly too far and engaged by the stops, but the mechanism will prevent the over-feeding of the sheet by such an amount as to cause the grippers to fail to engage it properly.

Having thus described my invention, I claim:

1. In mechanism for feeding sheets to a printing press or other sheet handling machine, a feed board over which the sheets pass, front lays movable to a position at the forward end of said feed board for front registering the sheets one after another, and a sheet arresting device normally ineffective with respect to properly fed sheets arranged to move upwardly from a level beneath the feed board to a position above the feed board slightly in advance of the operative position of the front lays and prior to the time the front lays assume their registering position to engage any misplaced sheet and prevent its being moved forward on the feed board substantially past the registering position.

2. In mechanism for feeding sheets in lapped relation to a printing press or other sheet handling machine, a feed board over which the stream of sheets passes, front lays pivotally mounted above the forward end of the feed board to swing into position at the front end of the feed board for front registering the sheets one after another, and a sheet arresting device arranged to move upwardly from a level beneath the feed board to a position above the feed board slightly in advance of the operative position of the front lays, whereby any sheet which is forwardly misplaced will be caught by said sheet arresting device and held against forward movement during at least a portion of the movement of said front lays backwardly to sheet registering position.

3. In mechanism for feeding sheets to a printing press or other sheet handling machine, a feed board over which the sheets pass, front lays movable to a position at the forward end of said feed board for front registering the sheets one after another, stops normally ineffective with respect to properly fed sheets mounted to move upwardly together from a position below the level of said feed board to a position above the level of the feed board slightly in advance of the operative position of the front lays and prior to the time the front lays assume their registering position, said stops being timed to move upwardly to their sheet arresting position after the front lays have been withdrawn and before the rear edge of the next preceding sheet has passed the stops.

4. In mechanism for feeding sheets in lapped relation to a printing press or other sheet handling machine, a feed board over which the stream of sheets passes, front lays movable to a position at the forward end of said feed board for front registering the sheets one after another, stops normally ineffective with respect to properly fed sheets mounted to swing together upon a transverse axis below the forward end of said feed board upwardly to a position above the level of the feed board slightly in advance of the operative position of the front lays'and prior to the time the front lays assume their registering position, said stops being timed to swing upwardly to their sheet arresting position directly after the front lays have been withdrawn to permit the sheet to pass to the printing press or other machine.

I-IEADLEY TOWNSEND BACKHOUSE. 

